Eisai Co.’s epilepsy drug Zonegran helped obese people lose weight, according to a study that shows the potential of another antiseizure medication to aid in weight reduction. Obese people who took 400 milligrams of Zonegran a day for a year had a 3.3 kilograms (7.3 pounds) greater weight loss than those on a placebo, according to the study published today in Archives of Internal Medicine. The efficacy was similar to Roche Holding AG (ROG)’s Xenical and Arena Pharmaceuticals Inc. (ARNA)’s Belviq. Side effects such as mood changes and memory problems occurred more frequently than with a placebo, the authors of the study at Duke University Medical Center in Durham, North Carolina, said. “The drug’s benefit-to-risk ratio needs thoughtful and cautious assessment,” the researchers said in the study.